Firefox does natively support creating text fragment links with a hidden configuration tweak.
First, type about:config in the address bar, followed by the enter key and continue at the warning prompt. Then search for fragments and tweak the following settings:
- Set
dom.text_fragments.create_text_fragment.enabledtotrueby double clicking on it. - The following of text fragment links can be enabled (as is default?) by setting
dom.text_fragments.enabledtotrueby double-clicking on it. - There is also a related timeout value, the function of which seems undocumented:
dom.text_fragments.create_text_fragment.timeout_seconds(default value5).